Wasp Duraline WLS 8400 ER Series, Руководство по продукции

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WLS 8400 Product Reference Guide GL-6
Data Matrix This error correcting, 2-dimensional matrix
symbology is capable of encoding various character
sets including strictly numeric data, alphanumeric
data and all ISO 646 (ASCII) characters, as well as
special character sets. The symbology has both error
detection and error correction features. Each Data
Matrix symbol consists of data regions, which
contain nominally square modules set out in a regular
array. A dark module is a binary 1 and a light module
is a binary 0. There is no specified minimum or
maximum for the X or Y dimension. The data region
is surrounded by a finder pattern, a perimeter to the
data region that is 1 module wide, which is
surrounded by a quiet zone on all four sides of the
symbol. Two adjacent sides are solid dark lines used
primarily to define physical size, orientation and
symbol distortion. The two opposite sides consist of
alternating dark and light modules. These are used
primarily to define the cell structure but also assist in
determining physical size and distortion.
There are 2 types of Data Matrix symbologies: ECC
000 - 140 with several available levels of
convolutional error correction, and ECC 200, which
uses Reed-Solomon error correction. For ISO/IEC
JTC 1/SC 31 purposes, only ECC 200 is
recommended. The intellectual property rights
associated with Data Matrix have been committed to
the public domain.
Data Structure The stipulation of the type of information that is
included in a bar code, such as its order and format.
Dead Zone An area within a scanner's field of view, in which
specular reflection may prevent a successful decode.
Decode To recognize a bar code symbology (e.g., UPC/EAN)
and then analyze the content of the specific bar code
scanned.
Decode Algorithm A decoding scheme that converts pulse widths into
data representation of the letters or numbers encoded
within a bar code symbol.